[MAPREDUCE-2470] Receiving NPE occasionally on RunningJob.getCounters() call

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.21.0
• Fix Version/s: 0.23.0
• Component/s: client

Environment

FreeBSD, Java6, Hadoop r0.21.0

• Hadoop Flags: Reviewed
• Assignee: Robert Joseph Evans
• Reporter: Aaron Baff
• Created: 03/May/11 22:08
• Updated: 15/Nov/11 00:48
• Resolved: 25/May/11 09:09

Description

This is running in a Java daemon that is used as an interface (Thrift) to get information and data from MR Jobs. Using JobClient.getJob(JobID) I successfully get a RunningJob object (I'm checking for NULL), and then rarely I get an NPE when I do RunningJob.getCounters(). This seems to occur after the daemon has been up and running for a while, and in the event of an Exception, I close the JobClient, set it to NULL, and a new one should then be created on the next request for data. Yet, I still seem to be unable to fetch the Counters. Below is the stack trace.

java.lang.NullPointerException
at org.apache.hadoop.mapred.Counters.downgrade(Counters.java:77)
at org.apache.hadoop.mapred.JobClient$NetworkedJob.getCounters(JobClient.java:381)
at com.telescope.HadoopThrift.service.ServiceImpl.getReportResults(ServiceImpl.java:350)
at com.telescope.HadoopThrift.gen.HadoopThrift$Processor$getReportResults.process(HadoopThrift.java:545)
at com.telescope.HadoopThrift.gen.HadoopThrift$Processor.process(HadoopThrift.java:421)
at org.apache.thrift.server.TNonblockingServer$FrameBuffer.invoke(TNonblockingServer.java:697)
at org.apache.thrift.server.THsHaServer$Invocation.run(THsHaServer.java:317)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:619)